Microsoft Fixes Windows Defender Bug That Throttled Firefox
Jakob Aylesbury / 2 years ago
Windows has addressed a bug with Windows Defender which caused performance issues with the Firefox browser.
Windows Defender KneeCapping Firefox
Windows Defender is Microsofts inbuilt anti-malware service with Windows and for more than 5 years it has been causing problems with the Firefox browser. Many users have complained that Windows Defender had been putting unnecessary strain onto the CPU whilst using Firefox and causing it to become laggy and unresponsive. After 5 years Mozilla, which is behind the browser, have discovered the source of the issue and Microsoft have themselves addressed the issue.
What Caused The Issue?
The issue was discovered in March and shared on Bugzilla where it was found that MsMpEng.exe was executing a high number of calls to the OS kernel’s VirtualProtect function whilst using Firefox. Virtual Protect is a process that “Changes the protection on a region of committed pages in the virtual address space of the calling process.” and was doing a lot of useless computation upon each event. This combination caused Firefox to use more CPU than necessary and in turn slowed it down.
As of today, Microsoft has released an update that remedies this issue and Firefox users are urged to update.
Have you encountered this issue? Let us know in the comments.
